Concrete-mixer.



No. 646,544. Patented Apr. 3, I900.

H. MISCAMPBELL.

CONCRETE MIXER.

(Application filed July 5, 1899.)

.(No Model.)

, E 1 i 4 I k\ i K I/II/IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII WITNESSES s EI I 2 1 g INVENTOR a UNITED I STATES PATENT OFFICE.

HUGH MISCAMPBELL, OF DULUTH, MINNESOTA.

CONCRETE-MIXER.

SPECIFICATION forming part of Letters Patent No. 646,544, dated April 3,1900-.

I Application filed July 5, 1899. I Serial No. 722,823. (Nomodeld T aZlwhom it may concern:

Be it known that I, HUGH MISOAMPBELL, a citizen of the United States,residing at Duluth,'in the county ofSt. Louis-and State of Minnesota,have invented certain new and .useful Improvements in Concrete-Mixers,

rnixer made in accordance with my invention, and Fig. 2 represents avertical central section through the same.

1 in the drawings represents a base upon which is revolubly mounted aplatform 2.

Sis a vertical shaft or standard, and 4 a scraper.

In carrying out my invention I form the base 1 preferably of a series ofbeams, as 5 5, and cross connecting-beams 6 6, having their uppersurfaces flush with each other. Upon the said frame 1 and aboutcentrally thereof I mount a standard or shaft 3, having a pedestal orfoot portion 7, adapted to have a broad bearing upon the base 1. Abovethe pedestal 7 a revolving floor is arranged at a suitable height fromthe base 1 and having preferably ball-bearings interposed between it andthe said base and between it and the said pedestal. The pedestal 7 ispreferably provided with an annular groove or recess, as at 8, adaptedto receive antifriction-balls 9, said balls 9 also engaging a ball raceor groove 10, secured to the under side of the floor 2. A secondball-race, as 11, is secured to the bottom of the floor and engageballs, as 12, said balls running in a grooveior ball-race 13, mountedupon the. frame 1. In order to still further steady the floor 2, it isprovided upon its upper surface with a ball-race 14, carrying balls 15,which engage an annular groove in the collar 16 upon a vertical shaft 3.This arrangement of bearings gives a proper support to the table andprevents the table from tipping in one direction.

Thefioor 2 is preferably formed of an under framework composed of radialbars or beams 17 17, preferably of T-irons, and a circumferential ringportion, as 18, secured to the outer ends of the said radial beams 1717. The floor proper rests upon the framework and is provided withupwardly-turned flanges a't its'outer edge, .as 19, to hold the materialupon the floor. An inner drum or flange 20 is also secured upon thefloor 2, surrounding the collar 16 and ball-bearings beneath it, toprevent the concrete from coming in contact with these parts, The fioor2 is also provided with a trap, as at'21, the door 22 of which ispivotally mounted, so that the trap may-be opened at any suitable timefor discharging the contents of the floor. The shaft carrying the door22 extends to the periphery of the iioor 2 and is provided with a handoperating-wheel, as23. The saidshaft also car- .ries a ratchet-wheel 24,which is adapted to be engaged by a pawl 25 upon the fioor 2, the saidpawl controlling the movement of the shaft through the agency of theratchetwheel 24.

The material may be supplied to the floor by means of a suitable chuteor trough, as 26, which extends over the edge of the floor, but does nottouch the same.

In order to even the material placed upon the floor, I provide anevening or spreading board 4, which has shaft extensions at its ends,one of said extensions finding a bearing in the standard 3, While theother extension is provided with a handle 27, bywhich the board mayberaised or lowered upon its bearings. The-"shaft extension on the outerend of the board" finds a suitable bearing in a standard '28, secured tothe base-frame 1. A pawl 20 upon the said standard 28 engages aratchet-wheel 30 on the shaft extension, so as to control the positionof the evening and shaping board. It will be apparent that after thematerial has been placed upon the floor 2 by lowering theevening-board 4it may be better spread over the surface of the floor.

After the contents of the floor have been thoroughly mixed and is incondition to be discharged the trap 21 may be opened and the board 4lowered to a still greater degree, so as to scrape everything from theboard out through the trap 21. It will of course be borne in mind thatthe spreading-board 4 is stationary, while the floor 2 rotates.

In order to thoroughly mix the material placed upon the floor, Ipreferably mount a rod or circular bar 31 31 eccentrically with respectto the floor, as clearly seen in Fig. 1 of the drawings. The ring orcircular rod 31 is supported by means of bars or rods 32 32, which arecarried by means of a collar 33, movably mounted upon the standard 3.The said collar is preferably splined upon the said shaft, so that,although it maybe moved vertically for raising and lowering thering-bar, it will not rotate upon the said standard. Secured to thecircular rod 31 are a series of downwardly-extending arms 34 34,carrying at their lower ends mixing-blades or stirring paddles or plows35. These mixing-blades may be secured at intervals around the circularrod 31 and set at different angles, as indicated in Fig. 1 of thedrawings, so as to completely come in contact with the material upon thefloor 2 and thoroughly mix the same. As an additional mixing means anauxiliary rod-or bar, as 36, may be secured to the ring 31, the saidauxiliarybar being also provided witha series of stirrers ormixing-paddles, as 37 37. The arms 34 of the mixing-blades arepreferably adjustably secured to their supporting-bars,being clampedthereon by means of suitable nuts, as 38 38, so that by loosening thenuts 38 the standards may be arranged so that the blades will extend inany desired angle, and by tightening the nuts again they will be held intheir adjusted positions.

In manipulating the machine it is desirable to have means for raisingthe mixingblades from the floor at certain times, and for this purpose Imount a lever, as 39, upon a bracket 40, secured to the upper end of thestandard 3. The lower end of the lever 39 is preferably bifurcated andadapted to engage projections or studs 41 41 upon the collar- 33. Bydepressing the outer end of the lever 39 the collar will be lifted andthe blades thus carried to the desired height above the floor 2. Thesaid blades of course can be lowered at any time bylifting the outer endof the lever 39.

It is desirable to rotate the floor 2 with respect to the mixing-bladesso as to completely stir up and mix the material on the said board, andfor this purpose I preferably provide a groove around the outerperiphery of the floor 2, as at 42. The groove may be made of wood or ofmetal or any desired material and may be engaged by an actuatingcable,as 43, which receives its motion from any suitable source of power. Itwill be apparent that cog-teeth might be substituted for the groove 42and the said cog-teeth be engaged by suitable gear-wheels for rotatingthe floor 2 without departing from the spirit of my invention. It willbe seen that instead of rotating the platform 2 the standard 3 might berotated, the floor being held stationary, thus moving thestirring-blades through the material to be mixed.

In using the concrete-mixer the mixingblades would be raised from thefloor at first. The materials necessary for the composition will then beplaced upon the floor 2 and the spreading board 4 lowered suflicientlyto spread the same evenly over the floor. The mixing-blades will nextbelowered, so as to thoroughly stir the contents of the floor as may bedesired. After the material has been completely mixed the trap 21 isopened and the scraping-board at is lowered its full extent, so as tocompletely scrape all the contents of the said floor through the trap21. While thus mixing the material, water or liquids which may benecessary can be safely sprayed upon the floor during the operation ofthe mechanism until the desired consistency of the concrete or othermaterial which may be mixed is attained.

It will be apparent that a machine of this kind is completely within thecontrol of the operator both as to mixing the material and distributingthe same from the floor.

Having now described my invention, What Iclaim as new, and desire tosecure by Letters Patent, is-

1. In a concrete-mixer, the combination with a suitable base, of arevolving floor mounted thereon, the said floor being pro-' vided with atrap for discharging the concrete at a suitable time, a spreading-boardprovided above the floor, its axis being arranged radially thereto, thesaid board passing over' the said trap and being adapted to spread thematerial evenly upon the whole of the floor,- and being also adaptedwhen lowered sufiiciently, to scrape the concrete carried by the floor,through the trap therein, substantially as described.

2. In a concretemixer, the combination with a suitable base, of arevolving floor mounted thereon, said floor being provided with an outerperipheral flange, and an inner peripheral drum for retaining theconcrete upon the floor, an evening scraping-board pivotally mountedabove the said floor, means for raising and lowering the same, asuitable frame mounted above the said floor and carrying a series ofstirring-blades, and means for raising and lowering the said frame andblades with respect to the said floor, substantially as described.

3. In a concrete-mixer, the combination with a base, of a standardmounted thereon, a revolving floor adapted to rotate about the saidstandard, an adjustable frame mounted upon the said standard, a splinedcollar for In testimony whereof I hereunto affix my signature inpresence of two witnesses.

HUGH MISCAMPBELL.

Witnesses:

JAMES T. WATSON, A. C. VoLK.

